OFFSET
1,2
COMMENTS
Column 4 of A252976
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = (29/479001600)*n^12 + (29/8870400)*n^11 + (3083/43545600)*n^10 + (233/290304)*n^9 + (73739/14515200)*n^8 + (48151/2419200)*n^7 + (2494049/43545600)*n^6 + (31657/483840)*n^5 - (1169489/10886400)*n^4 - (1024151/1814400)*n^3 + (2116423/831600)*n^2 - (601/27720)*n - 1
EXAMPLE
Some solutions for n=4
..0..1..1..1....0..1..2..3....0..0..0..1....0..1..2..2....0..0..1..2
..0..1..1..1....0..1..2..3....1..1..1..2....0..1..2..2....0..1..2..2
..0..1..2..2....1..2..2..3....2..2..2..2....1..1..2..3....1..2..2..2
..0..1..2..3....1..2..3..3....2..2..3..3....1..2..2..3....2..3..3..3
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 25 2014
STATUS
approved